HIV infection causes systemic immune inflammation, and increases the risk for cardiovascular (CVD) disease even among those on virologically suppressive anti-retroviral treatment (ART). We performed a biostatistical analysis and screen of candidate cellular and plasma biomarkers for association with carotid artery intima-media thickness (CIMT), independent of traditional CVD risk factors such as age, gender, systolic blood pressure (SBP), lipid levels, smoking and diabetes. We conducted a multi-stage analysis based on a cross-sectional study of CVD risk in HIV-infected subjects age >45 years on ART for >6 months. The goal of this analysis was to identify candidate cellular and plasma biomarkers of CIMT in HIV-1 infected adults. We further sought to determine if these candidate biomarkers were independent of traditional CVD risk factors previously identified in HIV negative adults. High-resolution B-mode ultrasound images of the right common carotid common artery (CCA) were obtained. Plasma soluble inflammatory mediators, cytokines and chemokines were detected. Monocytes were defined by CD14/CD16 expression, and CD8+ T-cell activation by CD38/HLA-DR expression. Subjects were a median of 49.5 years old, 87% male, had a CIMT of 0.73 mm, FRS of 6%, a median viral load of 48 copies/mL, and CD4+ T cell count of 479 cells/μL. Soluble VCAM-1, and expansion of CD14dimCD16− monocytes each associated with higher CIMT independently of age and SBP. These factors are distinct components of a shared atherogenic process; 1) vascular endothelial molecular expression and 2) vascular monocytes that enter into the vascular endothelium and promote atherosclerotic plaque.
HIV; Carotid intima-media; CIMT; Cardiovascular disease; Framingham risk score; Biomarker; Screen; Regression; CD14; Monocytes; VCAM-1; Cytokines
While experiments in animals demonstrate neurotoxic effects of particulate matter (PM) and ozone (O3), epidemiologic evidence is sparse regarding the relationship between different constituencies of air pollution mixtures and cognitive function in adults. We examined cross-sectional associations between various ambient air pollutants [O3, PM2.5 and nitrogen dioxide (NO2)] and six measures of cognitive function and global cognition among healthy, cognitively intact individuals (n=1,496, mean age 60.5 years) residing in the Los Angeles Basin. Air pollution exposures were assigned to each residential address in 2000–06 using a geographic information system that included monitoring data. A neuropsychological battery was used to assess cognitive function; a principal components analysis defined six domain-specific functions and a measure of global cognitive function was created. Regression models estimated effects of air pollutants on cognitive function, adjusting for age, gender, race, education, income, study and mood. Increasing exposure to PM2.5 was associated with lower verbal learning (β = −0.32 per 10 ug/m3 PM2.5, 95% CI = −0.63, 0.00; p = 0.05). Ambient exposure to NO2 >20 ppb tended to be associated with lower logical memory. Compared to the lowest level of exposure to ambient O3, exposure above 49 ppb was associated with lower executive function. Including carotid artery intima-media thickness, a measure of subclinical atherosclerosis, in models as a possible mediator did not attenuate effect estimates. This study provides support for cross-sectional associations between increasing levels of ambient O3, PM2.5 and NO2 and measures of domain-specific cognitive abilities.
air pollution; cognitive dysfunction; dementia; particulate matter; ozone; verbal learning
The long-held belief that outcome data from intervention trials in men are generalizable to women has created the framework in which the primary prevention of coronary heart disease (CHD) in women is viewed. However, over the past decade, data has accumulated to refute such a supposition of generalizability. These lines of evidence concern the sex-specific efficacy of CHD primary prevention therapies and timing of postmenopausal hormone replacement therapy (HRT) initiation according to age and/or time-since-menopause as modifiers of efficacy and risk. Although the standard primary prevention therapies of statins and aspirin reduce CHD in men, neither therapy reduce CHD, and more importantly total mortality in women under primary prevention conditions. On the other hand, HRT significantly reduces both CHD and total mortality in primary prevention when HRT is initiated in women <60 years old and/or <10 years-since-menopause. Herein, the efficacy of the commonly used therapies for the primary prevention of CHD in women, statins, aspirin and postmenopausal HRT is discussed. In part 2 of this series the comparative risks of these therapies are discussed.
hormone therapy in women; statins; timing hypothesis; women and CHD prevention; 31 meta-analyses
Blunted diurnal cortisol variation has been associated with overt cardiovascular disease in adults. The relationship between the diurnal cortisol variation and subclinical atherosclerosis in youth has yet to be investigated. The objectives of this study were to: 1) determine the relationship between overnight cortisol measures and CIMT in overweight and obese, African-American and Latino children; 2) assess ethnic differences in these relationships and 3) explore whether overnight cortisol and CIMT relationships were independent of inflammatory markers, C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α).
One hundred and fifty-six overweight and obese African-American and Latino children (ages 8–17, 86M/70F, 55 African-American /101 Latino) underwent measures of CIMT by B-mode ultrasound, nocturnal cortisol rise (NCR=salivary cortisol rise from 2200hrs to awakening at 0530hrs), cortisol awakening response (CAR=salivary cortisol from time of awakening to 30 min later), fasting serum cortisol and overnight urinary free cortisol.
Using linear regression, salivary cortisol0530hrs and NCR were negatively associated with CIMT (βstandardized = −0.215 and −0.220, p<0.01) independent of age, height, percent body fat, ethnicity and systolic blood pressure. Nocturnal salivary cortisol2200hrs, morning serum cortisol, and overnight urinary free cortisol were not associated with CIMT. Using ANCOVA, participants with LOW NCR (NCR <0.44µg/dL, n=52) had significantly greater CIMT than those with HIGH NCR (NCR ≥0.91 µg/dL, n=52; 0.632±0.008 vs. 0.603±0.008mm p=0.01) after controlling for covariates. Ethnicity was independently associated with CIMT, whereby African-American children had greater CIMT than Latino children (−0.028±0.009, p=0.006). The relationships between cortisol measures and CIMT did not differ between the two ethnic groups (all pinteraction=0.28–0.97). CRP, IL-6 and TNF-α were not associated with CIMT (p>0.05). IL-6 was inversely related to NCR (r=−0.186, p=0.03), but it did not explain the relationship between NCR and CIMT.
Salivary cortisol0530hrs and NCR, but not CAR, nocturnal salivary cortisol 2200hrs, morning serum cortisol or overnight urinary free cortisol, were associated with CIMT, independent of relevant covariates, including inflammatory factors. A low awakening salivary cortisol or a blunted NCR may be related to increased atherosclerosis risk in overweight and obese minority youth. These findings support adult studies suggesting flattened daytime diurnal cortisol variation impacts cardiovascular disease risk.
Obesity; cardiovascular risk; carotid artery; intima media thickness; cortisol
To determine whether long-term isoflavone soy protein (ISP) supplementation affects endometrial thickness and rates of endometrial hyperplasia and cancer in postmenopausal women.
In this randomized, double-blind, placebo-controlled trial, 350 postmenopausal women 45–92 years of age were randomized to a total daily dose of 154 mg of ISP or a milk protein matched placebo for a 3-year period. Women with a surgically absent uterus were excluded from the analysis (final study population: n=224). The main outcome measures were the mean change in endometrial thickness on transvaginal ultrasound from baseline until up to 36 months of follow-up; the incidence of endometrial sampling, endometrial hyperplasia and endometrial cancer.
A total of 666 visits among 224 participants were evaluated. Treatment groups did not significantly differ on the mean baseline or on-trial changes in endometrial thickness. Of the 103 placebo-treated participants, 7 (6.8%) underwent an endometrial biopsy; 6 (85.7%) of these biopsies were benign. One woman in the placebo group was diagnosed with complex endometrial hyperplasia with atypia and underwent a hysterectomy. The pathology result from this surgery was Stage IB endometrial cancer. Of the 121 participants in the soy group, 9 (7.4%) underwent an endometrial biopsy. The results were benign in all 9 cases (100%). Although the rate of hyperplasia / malignancy was higher in the placebo group (14.3% versus 0%), the difference was not statistically significant.
Three-year isoflavone soy protein (ISP) supplementation has no effect on endometrial thickness or rates of endometrial hyperplasia and cancer in postmenopausal women.
LEVEL OF EVIDENCE
Isoflavones; menopause; endometrium; randomized controlled trial
Among 127 HIV-infected women, the magnitude of HDLc increases after HAART initiation predicted the magnitude of concurrent decreases in inflammation biomarkers. After HAART initiation, changes in LDLc and inflammation were unrelated. In the same population, predicted risk of coronary heart disease based upon levels of standard clinical risk factors was similar before and after HAART treatment. Thus, it remains unknown whether short-term treatment-related changes in standard risk factors may appreciably change risk of CVD.
lipids; HAART; HIV infection; inflammation
To determine the association between birth weight and carotid artery intima-media thickness (CIMT), a measure of atherogenesis, in a population of 11-year-old children.
CIMT measured by high-resolution ultrasound, and birth registry data were available for 670 children of the Southern California Children’s Health Study. Multivariate regression analyses were performed to investigate the association between birth weight and CIMT, with adjustment for child’s health status and lifestyle, pregnancy information, and parental health.
Mean CIMT was 0.57 mm (SD 0.04). We found a nonlinear association between birth weight and CIMT, with an increase in CIMT of 0.014 mm in the fifth (P value .01) compared with the third birth weight quintile. These associations were robust in subsample analyses in children considered normal-weight by gestational age or in term-born children. No significant association with CIMT was found for the lowest quintile.
Greater birth weight was significantly associated with increased CIMT at age 11 years. No evidence for an impact of lower birth weight was found. The predictive value of childhood CIMT on future cardiovascular outcomes is largely unknown, but strong associations between childhood cardiovascular disease risk factors and adult vascular disease suggest that increased CIMT in childhood may be clinically important.
Background and Purpose
Although epidemiological and experimental studies suggest that dietary intake of soy may be cardioprotective, use of isoflavone soy protein (ISP) supplementation as a primary preventive therapy remains unexplored. We determined whether ISP reduces subclinical atherosclerosis assessed as carotid artery intima-media thickness (CIMT) progression.
In a double-blind, placebo-controlled trial, 350 postmenopausal women 45–92 years of age without diabetes and cardiovascular disease (CVD) were randomized to 2 evenly divided daily doses of 25 g soy protein containing 91 mg aglycon isoflavone equivalents or placebo for 2.7-years.
Overall, mean (95% confidence interval) CIMT progression rate was 4.77(3.39–6.16) μm/year in the ISP group and 5.68(4.30–7.06) μm/year in the placebo group. Although CIMT progression was reduced on average by 16% in the ISP group relative to the placebo group, this treatment effect was not statistically significant (p=0.36). Among the subgroup of women who were randomized within 5 years of menopause, ISP participants had on average a 68% lower CIMT progression rate than placebo participants 2.16(−1.10–5.43) vs. 6.79(3.56–10.01) μm/year, p=0.05). ISP supplementation had a null effect on women who were >5 years beyond menopause when randomized. There were no major adverse events from ISP supplementation.
ISP supplementation did not significantly reduce subclinical atherosclerosis progression in postmenopausal women. Subgroup analysis suggest that ISP supplementation may reduce subclinical atherosclerosis in healthy young (median age, 53 years) women at low-risk for CVD who were <5 years postmenopausal. These first trial results of their kind warrant further investigation.
Atherosclerosis; Cardiovascular disease; Intima-media thickness; Isoflavones; Menopause; Soy; Women
To determine whether self-reported menopausal symptoms are associated with measures of subclinical atherosclerosis.
Multi-center, randomized controlled trial.
Recently menopausal women (n=868) screened for the Kronos Early Estrogen Prevention Study (KEEPS).
Cross sectional analysis.
Main Outcome Measures
Baseline menopausal symptoms (hot flashes, dyspareunia, vaginal dryness, night sweats, palpitations, mood swings, depression, insomnia, irritability), serum estradiol (E2) levels and measures of atherosclerosis were assessed. Atherosclerosis was quantified using Coronary Artery Calcium (CAC) Agatston scores (n=771) and Carotid Intima-Media Thickness (CIMT). Logistic regression model of menopausal symptoms and E2 was used to predict CAC. Linear regression model of menopausal symptoms and E2 was used to predict CIMT. Correlation between length of time in menopause with menopausal symptoms, estradiol (E2), CAC, and CIMT were assessed.
In early menopausal women screened for KEEPS, neither E2 nor climacteric symptoms predicted the extent of subclinical atherosclerosis. Palpitations (p=0.09) and depression (p=0.07) approached significance as predictors of CAC. Other symptoms of insomnia, irritability, dyspareunia, hot flashes, mood swings, night sweats, and vaginal dryness were not associated with CAC. Women with significantly elevated CAC scores were excluded from further participation in KEEPS; in women meeting inclusion criteria, neither baseline menopausal symptoms nor E2 predicted CIMT. Years since menopause onset correlated with CIMT, dyspareunia, vaginal dryness and E2.
Self-reported symptoms in recently menopausal women are not strong predictors of subclinical atherosclerosis. Continued follow-up of this population will be performed to determine if baseline or persistent symptoms in the early menopause are associated with progression of cardiovascular disease.
KEEPS; estrogen; cardiovascular; menopause; CAC; CIMT; palpitations; depression
To determine whether changes in standard and novel risk factors during the ACT NOW trial explained the slower rate of CIMT progression with pioglitazone treatment in persons with prediabetes.
Methods and Results
CIMT was measured in 382 participants at the beginning and up to three additional times during follow-up of the ACT NOW trial. During an average follow-up of 2.3 years, the mean unadjusted annual rate of CIMT progression was significantly (P=0.01) lower with pioglitazone treatment (4.76 × 10−3 mm/year, 95% CI, 2.39 × 10−3 – 7.14 × 10−3 mm/year) compared with placebo (9.69 × 10−3 mm/year, 95% CI, 7.24 × 10−3 – 12.15 × 10−3 mm/year). High-density lipoprotein cholesterol, fasting and 2-hour glucose, HbA1c, fasting insulin, Matsuda insulin sensitivity index, adiponectin and plasminogen activator inhibitor-1 levels improved significantly with pioglitazone treatment compared with placebo (P < 0.001). However, the effect of pioglitazone on CIMT progression was not attenuated by multiple methods of adjustment for traditional, metabolic and inflammatory risk factors and concomitant medications, and was independent of changes in risk factors during pioglitazone treatment.
Pioglitazone slowed progression of CIMT, independent of improvement in hyperglycemia, insulin resistance, dyslipidemia and systemic inflammation in prediabetes. These results suggest a possible direct vascular benefit of pioglitazone.
Carotid atherosclerosis progression; Impaired glucose tolerance; Insulin resistance; Inflammation; Pioglitazone
We examined serum lipids in association with carotid artery intima-media thickness (CIMT) in HIV-infected and HIV-uninfected women.
In 2003–4, among 1827 Women’s Interagency HIV Study participants, we measured CIMT and lipids (high-density lipoprotein cholesterol [HDL-c], low-density lipoprotein cholesterol [LDL-c], total cholesterol [TC], non-HDL-c). A subset of 520 treated HIV-infected women had pre-1997 lipid measures. We used multivariable linear regression to examine associations between lipids and CIMT.
In HIV-uninfected women, higher TC, LDL-c and non-HDL-c were associated with increased CIMT. Among HIV-infected women, associations of lipids with CIMT were observed in treated but not untreated women. Among the HIV-infected women treated in 2003–4, CIMT was associated both with lipids measured a decade earlier in infection, and with late lipid measurements.
Among HIV-infected women, hyperlipidemia is most strongly associated with subclinical atherosclerosis in treated women. Among treated women, the association appeared strongest early in the disease course.
cardiovascular diseases; carotid arteries; HAART; HIV; lipids
Background. The relationships between soluble CD14 (sCD14), endotoxin (lipopolysaccharide [LPS]), and progression of atherosclerosis have not been defined in human immunodeficiency virus (HIV) infection.
Methods. We retrospectively assessed serum sCD14 and LPS levels of 91 subjects in a prospective 3-year study of carotid artery intima-media thickness (CIMT) (AIDS Clinical Trials Group [ACTG] 5078), where subjects were enrolled as risk factor–controlled triads of HIV-uninfected (n = 36) and HIV-infected individuals with (n = 29) or without (n = 26) protease inhibitor (PI)–based therapy for ≥2 years. The primary end point was the yearly rate of change of CIMT (ΔCIMT).
Results. In multivariate analysis of the HIV-infected subjects, each 1 µg/mL above the mean of baseline serum sCD14 corresponded to an additional 1.52 µm/y (95% confidence interval, .07–2.98; P = .04) in the ΔCIMT. Every 100 pg/mL above the mean of baseline serum LPS corresponded to an additional 0.49 µm/y (95% confidence interval, .18–.81; P = .003) in the ΔCIMT. However, in univariate analysis in the HIV-uninfected group sCD14 (P = .33) and LPS (P = .27) levels were not associated with higher ΔCIMT. HIV infection and PI therapy were not associated with baseline serum LPS and sCD14 levels (P > .1).
Conclusions. Our data are among the first to suggest that serum biomarkers of microbial translocation (LPS) and macrophage activation (sCD14) predict subclinical atherosclerosis progression in HIV-infected persons.
Background and Purpose
To investigate whether the Framingham Cardiovascular Risk Profile (FCRP) and carotid artery intima-media thickness (CIMT) are associated with cortical volume and thickness.
Consecutive subjects participating in a prospective cohort study of aging and mild cognitive impairment enriched for vascular risk factors for atherosclerosis underwent structural MRI scans at 3T and 4T MRI at three sites. Freesurfer (v5.1) was used to obtain regional measures of neocortical volumes (mm3) and thickness (mm). Multiple linear regression was used to determine the association of FCRP and CIMT with cortical volume and thickness
152 subjects (82 men) were aged 78 (±7) years old, 94 had a CDR of 0, 58 had a clinical dementia rating (CDR) of 0.5 and the mean mini-mental status examination (MMSE) was 28 ± 2. FCRP score was inversely associated with total gray matter (GM) volume, parietal and temporal GM volume (adjusted p<0.04). FCRP was inversely associated with parietal and total cerebral GM thickness (adjusted p<0.03). CIMT was inversely associated with thickness of parietal GM only (adjusted p=0.04). Including history of myocardial infarction or stroke and radiologic evidence of brain infarction, or apoE genotype did not alter relationships with FCRP or CIMT.
Increased cardiovascular risk was associated with reduced GM volume and thickness in regions also affected by Alzheimer’s disease (AD), independent of infarcts and apoE genotype. These results suggest a “double hit” toward developing dementia when someone with incipient AD also has high cardiovascular risk.
Framingham cardiovascular risk profile; carotid intima media thickness; gray matter; cortical volume; cortical thickness; atrophy
Exposure to ambient air pollutants increases risk for cardiovascular health outcomes in adults. The contribution of childhood air pollutant exposure to cardiovascular health has not been thoroughly evaluated.
Methods and results
The Testing Responses on Youth study consists of 861 college students recruited from the University of Southern California in 2007–2009. Participants attended one study visit during which blood pressure, heart rate and carotid artery intima-media thickness (CIMT) were assessed. Self-administered questionnaires collected information about health and socio-demographic characteristics and a 12-hr fasting blood sample was drawn for lipid and biomarker analyses. Residential addresses were geocoded and used to assign cumulative air pollutant exposure estimates based on data derived from the U.S. Environmental Protection Agency’s Air Quality System (AQS) database. The associations between CIMT and air pollutants were assessed using linear regression analysis. Mean CIMT was 603 μm (± 54 SD). A 2 standard deviation (SD) increase in childhood (aged 0–5 years) or elementary school (aged 6–12) O3 exposure was associated with a 7.8 μm (95% CI −0.3, 15.9) or 10.1 μm (95% CI 1.8, 18.5) higher CIMT, respectively. Lifetime exposure to O3 showed similar but non-significant associations. No associations were observed for PM2.5, PM10 or NO2 although adjustment for these pollutants strengthened the childhood O3 associations.
Childhood exposure to O3 may be a novel risk factor for CIMT in a healthy population of college students. Regulation of air pollutants and efforts that focus on limiting childhood exposures continue to be important public health goals.
atherosclerosis; cardiovascular diseases; carotid arteries; epidemiology; pediatrics
The objective of this study was to examine the influence of persistence of the MetS (MetS) and its individual components over a 3-year period on carotid intima media thickness (CIMT) in overweight Latino children.
Ninety-seven healthy male and female overweight Latino children (mean age at baseline: 11.0±1.8 yrs) were assessed for MetS on four annual evaluations and classified according to the persistence of MetS: NEVER (0 annual visits with the MetS, n=53), INTERMITTENT (1 or 2 visits with the MetS, n=28), and PERSISTENT (3 or 4 visits with the MetS, n=16). CIMT was measured with high-resolution B-mode ultrasound (7.9±0.7 months after the most recent MetS assessment; mean age: 14.6±1.8 yr).
PERSISTENT MetS was associated with significantly higher CIMT (0.647mm±0.018 compared to (0.600mm±0.007 in those who NEVER had MetS, p<0.01). This difference remained significant after controlling for gender, baseline age, total fat mass, total lean tissue mass and insulin sensitivity. PERSISTENT high waist circumference and PERSISTENT high blood pressure were also significantly associated with higher mean CIMT, but these differences were no longer significant after controlling for total fat and lean tissue mass. Baseline systolic blood pressure and 2-hour glucose were significantly related to CIMT independent of all other MetS components (p<0.05).
Persistence of the MetS over a 3-year period was uniquely associated with increased CIMT during childhood. Children with hypertension, persistent abdominal adiposity and impaired glucose tolerance may also be at higher risk for elevated CIMT.
CIMT; obesity; children; MetS
To assess carotid artery intima media thickness (CIMT) change over two years in overweight Latino adolescents and examine its relationship to cardiometabolic risk.
72 healthy overweight male and female Latino adolescents (mean age: 14.5±1.7 yrs; mean BMI: 31.5±6.9 kg/m2) were evaluated at baseline and 2 years later for: CIMT by high resolution B-mode ultrasound, the metabolic syndrome and its features, body composition by DEXA and MRI, and glucose/insulin measures by fasting blood, and oral and intravenous glucose tolerance tests.
Baseline CIMT did not differ from 2-year follow-up; however 38 participants increased CIMT (0.017±0.003mm; +2.8%) and 34 decreased (-0.019±0.002mm; −3.1%). ANCOVA analyses showed that participants with CIMT progression had higher baseline LDL-cholesterol and total cholesterol (91.3±3.4 and 150.3±3.9mg/dL) compared with those with CIMT regression (78.1±3.6 and 135.6±4.2mg/dL, p<0.05), independent of sex, baseline CIMT, age, and height. In multivariate regression, LDL-cholesterol was the sole predictor of CIMT progression, but the effect was small (odds of CIMT progression increased by 3% for each 1 mg/dL higher baseline LDL-cholesterol [95% CI: 1.004-1.006, p=0.03].
These results indicate a high variability in the magnitude of CIMT change in growing overweight Latino youth and support the use of LDL-cholesterol to assess sub-clinical atherosclerosis risk in this population.
Obesity; Cardiovascular disease risk; Ultrasound imaging
Background and Purpose
Although plasma total homocysteine (tHcy) levels are associated with cardiovascular disease (CVD), it remains unclear whether homocysteine is a cause or a marker of atherosclerotic vascular disease. We determined whether reduction of tHcy levels with B-vitamin supplementation reduces subclinical atherosclerosis progression.
In this double-blind clinical trial, 506 participants 40–89 years of age with an initial tHcy >8.5 μmol/L without diabetes and CVD were randomized to high-dose B-vitamin supplementation (folic acid 5 mg + vitamin B12 0.4 mg + vitamin B6 50 mg) or matching placebo for 3.1 years. Subclinical atherosclerosis progression across 3 vascular beds was assessed using high-resolution B-mode ultrasonography to measure carotid artery intima-media thickness (primary outcome) and multidetector spiral computed tomography to measure aortic and coronary artery calcium (secondary outcome).
Although the overall carotid artery intima-media thickness progression rate was lower with B-vitamin supplementation than with placebo, statistically significant between-group differences were not found (p=0.31). However, among subjects with baseline tHcy≥9.1 μmol/L, those randomized to B-vitamin supplementation had a statistically significant lower average rate of carotid artery intima-media thickness progression compared with placebo (p=0.02); among subjects with a baseline tHcy <9.1 μmol/L there was no significant treatment effect (p-value for treatment interaction=0.02). B-vitamin supplementation had no effect on progression of aortic or coronary artery calcification overall or within subgroups.
High-dose B-vitamin supplementation significantly reduces progression of early stage subclinical atherosclerosis (carotid artery intima-media thickness) in well-nourished healthy B-vitamin “replete” individuals at low-risk for CVD with a fasting tHcy >9.1 μmol/L.
Atherosclerosis; Computed tomography; Folate; Homocysteine; Intima-media thickness; Randomized controlled trials; Vitamin B12
We assessed associations of herpes simplex virus types 1 and 2 (HSV-1 and -2), cytomegalovirus (CMV), and human herpesvirus 8 (HHV-8) infection with subclinical coronary atherosclerosis in 291 HIV-infected men in the Multicenter AIDS Cohort Study. Coronary artery calcium (CAC) was measured by non-contrast coronary CT imaging. Markers for herpesviruses infection were measured in frozen specimens collected 10-12 years prior to case identification. Multivariable logistic regression models and ordinal logistic regression models were performed. HSV-2 seropositivity was associated with coronary atherosclerosis (adjusted odds ratio [AOR] =4.12, 95% confidence interval [CI] =1.58-10.85) after adjustment for age, race/ethnicity, cardiovascular risk factors, and HIV infection related factors. Infection with a greater number of herpesviruses was associated with elevated CAC levels (AOR=1.58, 95% CI=1.06-2.36). Our findings suggest HSV-2 may be a risk factor for subclinical coronary atherosclerosis in HIV-infected men. Infection with multiple herpesviruses may contribute to the increased burden of atherosclerosis.
herpesvirus; HSV-2; atherosclerosis; HIV-1/AIDS; risk factors
HIV-infected patients have low vitamin D levels as well as an increase in cardiovascular (CVD) risk. We examined the relationship between vitamin D and three markers of arterial dysfunction among HIV-infected individuals on stable antiretroviral (ARV) therapy. Levels of 25-hydroxyvitamin D [25(OH)D] were assessed by chemiluminescent immunoassay (DiaSorin) in 100 enrollees into the Hawaii Aging with HIV-Cardiovascular Cohort Study, a cohort of HIV-infected subjects age ≥40 years on stable (≥6 months) ARV therapy. The relationships between 25(OH)D levels and brachial artery flow-mediated dilation (FMD), right common carotid artery intima-media thickness (cIMT), and coronary artery calcium (CAC) were examined. Analytical methods included Pearson's correlations, Kruskal–Wallis tests, relative risks, and linear regression models. The cohort was 86% male and 60% white with a median age of 52 years and CD4 of 510 cells/mm3. The median (Q1, Q3) level of 25(OH)D was 27.9 ng/ml (21.8, 38.3). There were 72 FMD, 50 cIMT, and 90 CAC measurements available for analyses. A significant correlation was observed between 25(OH)D levels and FMD (r=0.30, p=0.01) but not with cIMT (r=−0.05, p=0.76). In a linear regression model, Framingham risk score attenuated the relationship between FMD and 25(OH)D. Those with lower 25(OH)D levels were at slightly higher risk of having CAC (RR=1.02, p=0.04). Among those with CAC, lower 25(OH)D levels were not associated with higher CAC scores (p=0.36). Lower vitamin D levels are associated with evidence of subclinical arterial dysfunction in HIV-infected individuals. The significance of these findings warrants further investigation.
Inflammation and hemostasis perturbation may be involved in vascular complications of HIV infection. We examined atherogenic biomarkers and subclinical atherosclerosis in HIV-infected adults before and after beginning highly-active antiretroviral therapy (HAART).
In the Women's Interagency HIV Study (WIHS), 127 HIV-infected women studied pre- and post-HAART were matched to HIV-uninfected controls. Six semi-annual measurements of soluble CD14, tumor necrosis factor (TNF)-alpha, soluble interleukin (IL)-2 receptor, IL-6, IL-10, monocyte chemoattractant protein (MCP)-1, D-dimer, and fibrinogen were obtained. Carotid artery intima-media thickness (CIMT) was measured by B-mode ultrasound.
Relative to HIV-uninfected controls, HAART-naïve HIV-infected women had elevated levels of soluble CD14 (1945 vs 1662 ng/mL, Wilcoxon signed rank P<0.0001), TNF-alpha (6.3 vs 3.4 pg/mL, P<0.0001), soluble IL-2 receptor (1587 vs 949 pg/mL, P<0.0001), IL-10 (3.3 vs 1.9 pg/mL, P<0.0001), MCP-1 (190 vs 163 pg/mL, P<0.0001) and D-dimer (0.43 vs 0.31 µg/mL, P<0.01). Elevated biomarker levels declined after HAART. While most biomarkers normalized to HIV-uninfected levels, in women on effective HAART, TNF-alpha levels remained elevated compared to HIV-uninfected women (+0.8 pg/mL, P=0.0002). Higher post-HAART levels of soluble IL-2 receptor (P=0.02), IL-6 (P=0.05), and D-dimer (P=0.03) were associated with increased CIMT.
Untreated HIV infection is associated with abnormal hemostasis (e.g., D-dimer), and pro-atherogenic (e.g., TNF-alpha) and anti-atherogenic (e.g., IL-10) inflammatory markers. HAART reduces most inflammatory mediators to HIV-uninfected levels. Increased inflammation and hemostasis are associated with subclinical atherosclerosis in recently treated women. These findings have potential implications for long-term risk of cardiovascular disease in HIV-infected patients, even with effective therapy.
antiretroviral therapy; cardiovascular diseases; cytokines; hemostasis; HIV; inflammation
While global measures of cardiovascular (CV) risk are used to guide prevention and treatment decisions, these estimates fail to account for the considerable interindividual variability in pre-clinical risk status. This study investigated heterogeneity in CV risk factor profiles and its association with demographic, genetic, and cognitive variables.
A latent profile analysis was applied to data from 727 recently postmenopausal women enrolled in the Kronos Early Estrogen Prevention Study (KEEPS). Women were cognitively healthy, within three years of their last menstrual period, and free of current or past CV disease. Education level, apolipoprotein E ε4 allele (APOE4), ethnicity, and age were modeled as predictors of latent class membership. The association between class membership, characterizing CV risk profiles, and performance on five cognitive factors was examined. A supervised random forest algorithm with a 10-fold cross-validation estimator was used to test accuracy of CV risk classification.
The best-fitting model generated two distinct phenotypic classes of CV risk 62% of women were “low-risk” and 38% “high-risk”. Women classified as low-risk outperformed high-risk women on language and mental flexibility tasks (p = 0.008) and a global measure of cognition (p = 0.029). Women with a college degree or above were more likely to be in the low-risk class (OR = 1.595, p = 0.044). Older age and a Hispanic ethnicity increased the probability of being at high-risk (OR = 1.140, p = 0.002; OR = 2.622, p = 0.012; respectively). The prevalence rate of APOE-ε4 was higher in the high-risk class compared with rates in the low-risk class.
Among recently menopausal women, significant heterogeneity in CV risk is associated with education level, age, ethnicity, and genetic indicators. The model-based latent classes were also associated with cognitive function. These differences may point to phenotypes for CV disease risk. Evaluating the evolution of phenotypes could in turn clarify preclinical disease, and screening and preventive strategies.
Background. Cytomegalovirus (CMV) infection has been implicated in immune activation and accelerated progression of immunodeficiency from human immunodeficiency virus (HIV) coinfection. We hypothesized that CMV is associated with vascular disease in HIV-infected adults.
Methods. In the Women's Interagency HIV Study, we studied 601 HIV-infected and 90 HIV-uninfected participants. We assessed the association of CMV immunoglobulin G (IgG) level with carotid artery intima-media thickness, carotid artery distensibility, Young's elastic modulus, and blood pressures. Multivariable models adjusted for age, race/ethnicity, smoking, diabetes, and body mass index.
Results. Mean CMV IgG levels were higher in HIV-infected women compared with HIV-uninfected women (P < .01). Among HIV-infected women, higher CMV IgG level was associated with decreased carotid artery distensibility (P < .01) and increased Young's modulus (P = .02). Higher CMV IgG antibody level was associated with increased prevalence of carotid artery lesions among HIV-infected women who achieved HIV suppression on antiretroviral therapy, but not among viremic or untreated HIV-infected women. Adjustment for Epstein–Barr virus antibody levels and C-reactive protein levels had no effect on the associations between CMV IgG levels and vascular parameters.
Conclusions. Cytomegalovirus antibody titers are increased in HIV-infected women and associated with subclinical cardiovascular disease. Host responses to CMV may be abnormal in HIV infection and associated with clinical disease.
To evaluate associations between traditional cardiovascular disease (CVD) risk factors, inflammatory markers, and markers of HIV disease activity with ultrasonographic measures of CVD risk in patients with HIV who are not receiving antiretroviral therapy (ART).
Cross-sectional, baseline evaluation of ART-naïve HIV-infected individuals without known CVD or diabetes mellitus enrolled in a randomized ART treatment trial.
Prior to ART initiation, carotid artery intima-media thickness (CIMT) and brachial artery flow-mediated dilation (FMD) were measured. Additional parameters included CD4 cell count, HIV viral load, body composition, lipoproteins, and inflammatory markers. Associations with common CIMT, bifurcation CIMT, presence of carotid artery lesions, and brachial artery FMD were evaluated.
The 331 enrolled subjects were a median (1st–3rd quartile) of 36 (28–45) years old. Common and bifurcation CIMT values were higher and lesions more prevalent with older age (p <0.001). FMD was lower with older age (p =0.009). Those with a Framingham Risk Score >6%/10 years (N =44) had higher common and bifurcation CIMT (p <0.001), carotid lesion prevalence (p <0.001), and lower FMD (p =0.035). Independent associations with common CIMT were identified for increasing age, height, weight, small LDL particles, and black race; these were similar for bifurcation CIMT. Presence of carotid artery lesions was associated with increasing age, presence of metabolic syndrome, interleukin-6, and lower HIV-1 RNA.
In a contemporary cohort of ART-naive HIV-infected individuals, ultrasonographic measures of CVD risk were more strongly associated with traditional risk factors than CD4 cell counts, HIV replication, or inflammatory markers.
atherosclerosis; carotid arteries; endothelial function; human immunodeficiency virus; inflammation